The present invention is directed to a tip trimmer assembly for trimming the tip off of a nozzle of a caulking gun cartridge and, more specifically, to a tip trimmer assembly which is adapted for use between a manually actuated caulking gun handle and trigger assembly.
Caulking guns having an arrangement for trimming or cutting the tip of a cartridge nozzle are disclosed in U.S. Pat. Nos. 3,189,226 and 3,105,614. In each of these patents a blade having a projection is pivoted at the pivot point of the trigger and the trigger engages the protection projection to drive the cutting edge of the blade across at least one aperture in the handle. U.S. Pat. No. 4,135,644 discloses a caulking gun assembly in which a pair of cutting blades are integrally formed as part of a trigger of a caulking gun. U.S. Pat. No. 4,493,437 discloses a caulking gun having a tip trimmer assembly with a razor blade attached as a cutting element to a caulking gun trigger. U.S. Pat. No. 4,390,115 discloses a caulking gun trimming assembly in which the inside edges of a plurality of apertures are sharpened to provide shearing edges for trimming the tip of a caulking gun cartridge nozzle.
Each of the foregoing trimming assemblies rely on movement of the trigger relative to the handle to effect the desired trimming or shearing action and the shearing action is effected each time the trigger is squeezed regardless of whether a nozzle tip is being trimmed or not. Moreover, the trimming assemblies in each of the above-mentioned references must be provided at the time when the caulking gun is being manufactured and, with the exception of U.S. Pat. No. 4,390,115, the cutting blade in each of the other references is either formed as a part of or attached to the trigger or pivoted about the pivot point of the trigger.
The present invention provides an improved trimmer assembly which, although actuated by the trigger, is separate from the trigger and being a separate unit can be used to retro-fit existing caulking guns. Another advantage derived from having the tip trimmer assembly as a separate unit is that means are also provided to lock or secure the trimmer assembly in an open position and a closed position so the assembly can be moved to the open position when it is necessary to trim a tip from the cartridge nozzle. The trimmer assembly is automatically moved to the closed position after the tip is trimmed thereby securing the cutting edge internally of the handle until such time that its use is again required to trim another tip off of a cartridge nozzle. The present invention also provides a trimmer assembly having a replaceable blade as a cutting edge and a shaped body portion which extends outward of the handle and prevents the fleshy parts of an operators hand from being pinched between the trigger and the handle.